Duck-hunting whistles, ugly sweaters and 'The Big Lebowski' paraphernalia are just a few examples of strange and unique products made by small businesses.

They are just a few examples of the world of niche retailers - a place where small businesses and entrepreneurs can flourish.

Starting a small business with a crazy idea sometimes pays off.

"At the end of the day, it's what makes a retailer different that helps drive their business," says Kathy Grannis, spokeswoman for the National Retail Federation. "Companies that can separate themselves from the competition will usually always find customers who are eager and interested in what they have to sell."

But selling the strange and unique is not for everyone, especially if the merchandise is truly specialized. Many times, these businesses are created after a consumer sees a hole in the marketplace. But that's the key - making sure there is indeed a demand for the product. Entrepreneurs who have a clear picture of their target market and competitors as well as a strategy to keep customers coming back are more likely to succeed.